A complex medium is a system that has a large number of distinct chemical components. Particles in a complex medium vary widely in size and chemical profile. These media do not readily lend themselves to chemical analysis of specific constituent of group of constituents because the components of a complex medium are frequently difficult to separate. Examples of complex media include blood, seawater and crude petroleum.
There is a need for an efficient method of assaying a sample of a complex medium to determine the presence of a particular constituent. Efficient assaying of complex media will enhance chemical detection across a broad range of fields. For example, the medical practitioner will assess the presence of toxins in blood or sera with greater accuracy and specificity. The environmental practitioner will assess the presence of pollutants in a body of water with greater speed and resolution.
The present invention is a method that adds a tag to a constituent particle, separates the tag from the particle, passes the tag through a membrane, and then analyzes the collection of tags. The invention is distinct from the prior art as it passes tags through a membrane designed to accommodate the measurement of particles of disparate sizes and chemical profiles. The invention offers greater selectivity than the prior art because it allows the researcher to more narrowly focus molecular recognition by manipulating the membrane permeability and mass selectivity
A tag is an identifying marker that can be attached to and removed from a molecule without permanently altering the molecule. Tags are used to help identify a target molecule because it may be easier to detect and manipulate the tags than to detect and manipulate the target particle itself.
A membrane is a barrier that separates two phases and delineates the molecules that can pass between the two phases. The use of a membrane may conserve resources that the researcher would have expended using conventional methods of separation, e.g., distillation. Membrane structures vary according to the nature of the reactants and the properties of the molecules that are selected to pass between phases. Membranes may be homogenous or heterogenous, symmetric or asymmetric and solid or liquid. The researcher can charge the membrane, render it bipolar or neutral. Method of transport varies as well. The researcher can select a membrane that uses a charge, temperature or pressure gradient.
A detector is any apparatus capable of registering and/or quantifying the presence of a target.